Association of polymorphic variants of GRIN2A and GRIN2B genes with alcoholand tobacco abuse in patients with schizophrenia

Aim. To compare the frequency of genotypes for polymorphic variants of GRIN2A and GRIN2B genes in patients with schizophrenia and addictive behavior (alcohol / tobacco abuse) and in patients with schizophrenia without addictive behavior in the Slavic population of the Tomsk region. Materials and methods. The study included 219 inpatients with the established diagnosis of schizophrenia who received treatment in the clinics of Mental Health Research Institute and Tomsk Clinical Psychiatric Hospital. A history of alcohol / tobacco abuse was identified during a clinical interview and objective data collection. DNA was isolated from peripheral blood leukocytes by standard phenol - chloroform extraction. 15 single nucleotide polymorphisms (SNPs) in the GRIN2A gene and 9 polymorphisms in the GRIN2B gene were selected for genotyping. Allelic variants were determined by real-time polymerase chain reaction (PCR) with specific primers. The SPSS 17.0 software package was used for statistical data processing. The distribution of genotype frequency was assessed using the Pearson's chi(2) test with the Yates' correction and the Fisher's exact test. Results. Significant differences in the allele frequency for the rs9788936 polymorphism in the GRIN2A gene (chi(2) = 4.23, p = 0.04) and for the rs10845838 polymorphism in the GRIN2B gene (chi(2) = 4.27, p = 0.04) were reveled between the groups of patients with and without alcohol abuse. It was found that the polymorphic variant rs8049651 of the GRATA gene had a clear association (F = 8.06, p = 0.029) with the development of tobacco addiction in patients with schizophrenia. Conclusion. The study identified the association between alcohol abuse and the rs9788936 polymorphism in the GRIN2A gene and the rs10845838 polymorphism in the GRIN2B gene in patients with schizophrenia. The association between the rs8049651 and rs7190619 polymorphisms in the GRIN2A gene and the development of tobacco abuse in patients with schizophrenia was revealed.